Some are, some aren't. The current China "antitrust" flap is over ones that got really big without being extensions of the state, such as Tencent and Ant Financial. The classic big ones, such as Baowu (steel), Cosco (shipping), and China Railway Group (obvious), are directly state-owned. There are also large companies owned by provinces, regions, and cities. Most small and medium sized companies, though, are not state-owned. State ownership of almost everything was tried during the Mao era, and it didn't work.
The CCP insists on being the only major center of power in China. They're willing to tolerate capitalism until it generates companies big enough to push back. Those get taken over or converted to state ownership.
At a minimum, the CCP has full visibility into every company operating in China. They require taxes to be filed via government-provided software, and this software was found to contain backdoors.
It gets even more insidious when every company above a certain size (10? 15?) is required to hire a Party Officer for oversight.
Some are, some aren't. The current China "antitrust" flap is over ones that got really big without being extensions of the state, such as Tencent and Ant Financial. The classic big ones, such as Baowu (steel), Cosco (shipping), and China Railway Group (obvious), are directly state-owned. There are also large companies owned by provinces, regions, and cities. Most small and medium sized companies, though, are not state-owned. State ownership of almost everything was tried during the Mao era, and it didn't work.
The CCP insists on being the only major center of power in China. They're willing to tolerate capitalism until it generates companies big enough to push back. Those get taken over or converted to state ownership.